Citations

ABSTRACT: Despite the high prevalence of kidney involvement in patients with light chain (AL) amyloidosis, a significant knowledge gap exists in understanding how immunoglobulin light chains drive kidney injury. The chief reason is the lack of molecular data from high-quality kidney tissue samples from this patient population. The RAIN trial (NCT03168906) was a phase 2b randomized placebo-controlled, clinical trial that evaluated the efficacy of NEOD001, a monoclonal antibody targeting amyloid fibrils, versus placebo in patients with AL nephropathy. Before drug administration, renal biopsies were taken and analyzed. OBJECTIVE: Identifying amyloid-specific molecular signatures in kidney biopsy tissue. MATERIALS & METHODS: Renal biopsies were collected on all RAIN participants before randomization to NEOD001 or placebo. Clinical data was collected and correlated to histologic and molecular findings. Histologic assessment included a composite scarring injury score (CSIC) as determined by the degree of glomerular and tubulointerstitial scarring, and a novel amyloid score (AS), as quantified by the extent and distribution of amyloid deposition. Glomerular (G) and tubulointerstitial (TI) compartments were micro-dissected and sequenced separately. To identify enriched pathways in AL nephropathy, the expression data was compared to the glomerular and tubular expression profiles of healthy living donor (LD) from the Nephrotic Syndrome Study Network (NEPTUNE) study. Differentially expressed genes (DEGs) were determined . RESULTS: Ten patients were enrolled, randomized and treated in the RAIN trial (5 NEOD001 and five placeboes) before trial closure in April 2018. Kidney tissue was available in nine of the ten patients. Cluster analysis revealed two distinct patient clusters (G1 and G2) within the glomerular and TI compartments ( See Figure 1). Key clinical data pertaining to kidney function and biopsy morphology by compartment and cluster type were documented. Despite similar eGFR and degree of proteinuria, there was a significantly higher AS score in the TI compartment (6.5 vs. 4.5; p=0.0290) of G2 which was driven most entirely by an increase in mesangial and capillary wall amyloid deposition. Pathway Enrichment in G2 versus G1: Glomeruli showed activation of fibrotic pathways accompanied by a reduction in metabolic processes including gluconeogenesis, lipid transport and xenobiotics. There was an increase in canonical signaling of LPS/IL-1 that drives increased IL1 and TNF release from macrophages. Transcriptomic evidence of TNF activation was also noted in the TI compartment. Other enriched ingenuity canonical pathways to note in the TI included ‘coagulation system’, ‘GADD45 signaling’, ‘Wnt/Ca+ pathway’, ‘intrinsic prothrombin activation pathway’ among others. Of note, genes like BRCA and CDKN1A were enriched between G1 and G2, both of which have been associated with molecular mechanisms that underly certain neoplasms ( See Figure 2). Pathway enrichment in Amyloid kidney disease versus LD: IPA analysis identified unique activation signatures in the glomeruli and tubules. In the glomeruli, there was increased signaling of TNF, NFKB, IL33, IL-8 and IL15, consistent with an important inflammatory response. There was also an enrichment in pathways related to migration, adhesion and integrin signaling. PI3K/Akt signaling was also noted. Tubules showed increased activation of transcriptional regulators TP53, TP73 and PI3K/AKT signaling. Some gene regulators of cellular proliferation such as ABL1, BCL2 and AKT1 were found to be enriched in the amyloid group. CONCLUSIONS: While the RAIN trial closed prematurely and NEOD001 cannot be evaluated, the molecular data revealed the presence of two distinct molecular subtypes of AL nephropathy. Whether these distinct molecular subtypes reflect different stages of the disease along a continuous spectrum or are of unique prognostic entities in of themselves remains unclear. Detailed studies, of a larger cohort of patients including investigating diseased tissue at a single cell resolution can help identify the response of individual kidney cell types. Understanding the cellular responses of key cell types to injury from amyloid deposits could provide novel therapeutic targets to mitigate renal injury and improve patient outcomes. Based on this early work, targeting the PI3K/Akt pathway may be a worthy pursuit in this disease.

Abstract Background There is scarce data surrounding the epidemiology of invasive fungal infections (IFI) after pancreas transplantation (PT). Our centers’ PT protocols recommend universal fluconazole prophylaxis for at least 1 month, which is extended to 1 year for recipients who live in Coccidioides endemic areas. The purpose of our study was to evaluate the epidemiology of IFIs after PT while on our antifungal prophylaxis protocol. Methods A retrospective cohort study was performed among adult patients who underwent PT at Mayo Clinic sites in Arizona, Florida, or Minnesota between January 1, 2010 and December 31, 2020. IFI was defined based on EORTC/MSGERC criteria. The primary aim was to describe epidemiology and timing of IFI after PT, particularly in the context of the universal antifungal prophylaxis protocol. Results Among 482 pancreas transplant recipients, 35 developed IFIs (7.3%). All patients received antifungal prophylaxis per protocol for a median duration of 33 days (Figure 1). Median duration from time of transplant to IFI was 16 (IQR 10.5-28.2) days for Candida IFIs versus 529 (IQR 192.5-1195.0) days for non-Candida IFI. 20 IFIs (57.1%) were secondary to Candida species with 45% of these cases caused by either C. glabrata or C. krusei (Figure 2). 90% were on antifungal prophylaxis (85% fluconazole) at time of diagnosis of invasive candidiasis. All the Candida IFIs were intra-abdominal infections. Amongst the 15 non-Candida IFIs (42.9%), 9 were secondary to endemic mycoses and 4 were secondary to invasive molds. Conclusion Our study shows a high incidence of IFIs secondary to Candida, with few patients diagnosed with non-Candida IFIs (Figure 3). Non-Candida IFIs, mostly secondary to endemic mycoses, occurred more than a year after transplant. Patients are at highest risk for Candida IFIs within the first 30 days after PT, likely secondary to organ space surgical site infections, despite receipt of antifungal prophylaxis. Breakthrough invasive candidiasis occurred in 90% of cases. Though our study lacked a comparator group without prophylaxis, these data question the effectiveness of fluconazole prophylaxis after PT. Disclosures All Authors: No reported disclosures

Abstract Background Catheter-related bloodstream infection (CRBSI) is an important complication of long-term central venous catheters (CVCs) and is associated with high morbidity and cost. While line removal is optimal, it is not always feasible and is not without complications. Antibiotic lock therapy (ALT) may be an alternative strategy for line salvage, but the efficacy of this approach particularly among immunocompromised hosts is unknown. Methods We retrospectively reviewed adult patients with CRBSI managed with ALT between 2018 and 2022 at our tertiary medical center. We reviewed patient comorbidities, type and indications for CVC use, microbiology of CRBSI, ALT, and use of systemic antibiotics. Outcomes included 30-day mortality, 90-day microbiologic relapse (with same bacteria as index case), 90-day recurrent BSI (with different bacteria from index case), and adverse events. Results 86 patients were reviewed, a majority of whom were immunocompromised (91%) due to hematopoietic stem cell transplantation (85%) and thrombocytopenic (platelet count 36; IQR 17-112). 78% had tunneled CVC for indications including peri-transplant therapy (72%), chemotherapy (15%), and TPN (6%) (Table 1). The median time to CRBSI following CVC insertion was 45 days (IQR 19-86). Infections were frequently monomicrobial (80%) due to Gram-positive organisms (n=75) including coagulase-negative staphylococci and Enterococcus spp. The minority of Gram-negative (n=17) infections were due to E coli and Enterobacter spp. 94% of patients received systemic antibiotics and all patients received ALT for a median of 11 days [IQR 6-15] and 11.5 days [IQR 6-14], respectively (Table 2). The 30-day attributable mortality rate was low at 1%. Rates of 90-day microbiologic relapse (20%) and recurrent BSI (16%) were high, occurring at a median of 42 days (IQR 12-55) and 35 days (IQR 25-50) following completion of ALT, respectively (Table 3). Conclusion Despite high rates of microbiologic relapse and recurrent BSI, ALT may be an effective line salvage strategy extending the use of CVC by up to 30 days with minimal impact on mortality even among immunocompromised patients. Disclosures John C. O'Horo, Sr., MD, MPH, Janssen Pharmaceuticals.: Grant/Research Support|nference: Grant/Research Support

ABSTRACT Standardized approaches to phage susceptibility testing (PST) are essential to inform selection of phages for study in patients with bacterial infections. There is no reference standard for assessing bacterial susceptibility to phage. We compared agreement between PST performed at three centers: two centers using a liquid assay standardized between the sites with the third, a plaque assay. Four Pseudomonas aeruginosa phages: PaWRA01ø11 (EPa11), PaWRA01ø39 (EPa39), PaWRA02ø83 (EPa83), PaWRA02ø87 (EPa87), and a cocktail of all four phages were tested against 145 P . aeruginosa isolates. Comparisons were made within measurements at the two sites performing the liquid assay and between these two sites. Agreement was assessed based on coverage probability (CP 8 ), total deviation index, concordance correlation coefficient (CCC), measurement accuracy, and precision. For the liquid assay, there was satisfactory agreement among triplicate measurements made on different days at site 1, and high agreement based on accuracy and precision between duplicate measurements made on the same run at site 2. There was fair accuracy between measurements of the two sites performing the liquid assay, with CCCs below 0.6 for all phages tested. When compared to the plaque assay (performed once at site 3), there was less agreement between results of the liquid and plaque assays than between the two sites performing the liquid assay. Similar findings to the larger group were noted in the subset of 46 P . aeruginosa isolates from cystic fibrosis. Results of this study suggest that reproducibility of PST methods needs further development.

We investigated the link between enhancement of SI (by hyperinsulinemic–euglycemic clamp) and muscle metabolites after 12 weeks of aerobic (high-intensity interval training [HIIT]), resistance training (RT), or combined training (CT) exercise in 52 lean healthy individuals. Muscle RNA sequencing revealed a significant association between SI after both HIIT and RT and the branched-chain amino acid (BCAA) metabolic pathway. Concurrently with increased expression and activity of branched-chain ketoacid dehydrogenase enzyme, many muscle amino metabolites, including BCAAs, glutamate, phenylalanine, aspartate, asparagine, methionine, and γ-aminobutyric acid, increased with HIIT, supporting the substantial impact of HIIT on amino acid metabolism. Short-chain C3 and C5 acylcarnitines were reduced in muscle with all three training modes, but unlike RT, both HIIT and CT increased tricarboxylic acid metabolites and cardiolipins, supporting greater mitochondrial activity with aerobic training. Conversely, RT and CT increased more plasma membrane phospholipids than HIIT, suggesting a resistance exercise effect on cellular membrane protection against environmental damage. Sex and age contributed modestly to the exercise-induced changes in metabolites and their association with cardiometabolic parameters. Integrated transcriptomic and metabolomic analyses suggest various clusters of genes and metabolites are involved in distinct effects of HIIT, RT, and CT. These distinct metabolic signatures of different exercise modes independently link each type of exercise training to improved SI and cardiometabolic risk. Article Highlights We aimed to understand the link between skeletal muscle metabolites and cardiometabolic health after exercise training. Although aerobic, resistance, and combined exercise training each enhance muscle insulin sensitivity as well as other cardiometabolic parameters, they disparately alter amino and citric acid metabolites as well as the lipidome, linking these metabolomic changes independently to the improvement of cardiometabolic risks with each exercise training mode. These findings reveal an important layer of the unique exercise mode–dependent changes in muscle metabolism, which may eventually lead to more informed exercise prescription for improving SI.

Background:: Breast cancer is one of the leading causes of cancer deaths in women. Early diagnosis offers the best hope for a cure. Ductal carcinoma in situ is considered a precursor of invasive ductal carcinoma of the breast. In this study, we carried out microRNA sequencing from 7 ductal carcinoma in situ (DCIS), 6 infiltrating ductal carcinomas (IDC Stage IIA) with paired normal, and 5 unpaired normal breast tissue samples. We identified 76 miRNAs that were differentially expressed in DCIS and IDC. Methods:: Additionally, we provide preliminary evidence of miR-365b-3p and miR-7-1-3p being overexpressed, and miR-6507-5p, miR-487b-3p, and miR-654-3p being downregulated in DCIS relative to normal breast tissue. We also identified a miRNA miR-766-3p that was overexpressed in early-stage IDCs. The overexpression of miR-301a-3p in DCIS and IDC was confirmed in 32 independent breast cancer tissue samples. Results:: Higher expression of miR-301a-3p is associated with poor overall survival in The Can-cer Genome Atlas Breast Cancer (TCGA-BRCA) dataset, indicating that it may be associated with DCIS at high risk of progressing to IDC and warrants deeper investigation. Conclusion:: We also analyzed competing endogenous networks associated with differentially expressed miRNAs and identified LRRC75A-AS1 and MAGI2-AS3 as lncRNAs that potentially play an important role in early-stage breast cancers.

Aging and many illnesses and injuries impair skeletal muscle mass and function, but the molecular mechanisms are not well understood. To better understand the mechanisms, we generated and studied transgenic mice with skeletal muscle–specific expression of growth arrest and DNA damage inducible α (GADD45A), a signaling protein whose expression in skeletal muscle rises during aging and a wide range of illnesses and injuries. We found that GADD45A induced several cellular changes that are characteristic of skeletal muscle atrophy, including a reduction in skeletal muscle mitochondria and oxidative capacity, selective atrophy of glycolytic muscle fibers, and paradoxical expression of oxidative myosin heavy chains despite mitochondrial loss. These cellular changes were at least partly mediated by MAP kinase kinase kinase 4, a protein kinase that is directly activated by GADD45A. By inducing these changes, GADD45A decreased the mass of muscles that are enriched in glycolytic fibers, and it impaired strength, specific force, and endurance exercise capacity. Furthermore, as predicted by data from mouse models, we found that GADD45A expression in skeletal muscle was associated with muscle weakness in humans. Collectively, these findings identify GADD45A as a mediator of mitochondrial loss, atrophy, and weakness in mouse skeletal muscle and a potential target for muscle weakness in humans.

PURPOSE CNS progression or relapse is an uncommon but devastating complication of aggressive B-cell lymphoma. There is no consensus regarding the optimal approach to CNS prophylaxis. This study was designed to determine whether high-dose methotrexate (HD-MTX) is effective at preventing CNS progression in patients at high risk of this complication. PATIENTS AND METHODS Patients age 18-80 years with aggressive B-cell lymphoma and high risk of CNS progression, treated with curative-intent anti–CD20-based chemoimmunotherapy, were included in this international, retrospective, observational study. Cause-specific hazard ratios (HRs) and cumulative risks of CNS progression were calculated according to use of HD-MTX, with time to CNS progression calculated from diagnosis for all patients (all-pts) and from completion of frontline systemic lymphoma induction therapy, for patients in complete response at completion of chemoimmunotherapy (CR-pts). RESULTS Two thousand four hundred eighteen all-pts (HD-MTX; n = 425) and 1,616 CR-pts (HD-MTX; n = 356) were included. CNS International Prognostic Index was 4-6 in 83.4% all-pts. Patients treated with HD-MTX had a lower risk of CNS progression (adjusted HR, 0.59 [95% CI, 0.38 to 0.90]; P = .014), but significance was not retained when confined to CR-pts (adjusted HR, 0.74 [95% CI, 0.42 to 1.30]; P = .29), with 5-year adjusted risk difference of 1.6% (95% CI, –1.5 to 4.4; all-pts) and 1.4% (95% CI, –1.5 to 4.1; CR-pts). Subgroups were underpowered to draw definitive conclusions regarding the efficacy of HD-MTX in individual high-risk clinical scenarios; however, there was no clear reduction in CNS progression risk with HD-MTX in any high-risk subgroup. CONCLUSION In this large study, high-risk patients receiving HD-MTX had a 7.2% 2-year risk of CNS progression, consistent with the progression risk in previously reported high-risk cohorts. Use of HD-MTX was not associated with a clinically meaningful reduction in risk of CNS progression.

AbstractBackgroundUrinary Tract Infections are the most common post‐transplant infection and can have varied presentations. This study aimed to describe the outcomes of kidney transplant recipients with asymptomatic histologic pyelonephritis on allograft biopsy. Histologic Pyelonephritis was defined as neutrophil cast or neutrophilic tubulitis, interstitial infiltrates with predominant neutrophils, and no evidence of rejection or glomerulonephritis on biopsy.MethodsThe study included 123 kidney transplant recipients, of whom 95 underwent protocol biopsies, and 28 had biopsies for elevated creatinine within the first 2 years of a kidney transplant.ResultsThe mean age of the cohort was 55.3 years, with 52% females and 78% deceased donor transplants. The risk factors for asymptomatic histologic pyelonephritis were recipient female sex (OR 1.89, 1.3–2.7, diabetes mellitus (OR 2.479, 1.687–3.645), and deceased donation (OR 1.69, 1.098–2.63). The incidence of asymptomatic pyelonephritis on protocol biopsy was 1.7%, with 52% having positive urine cultures and Escherichia coli being the most common bacteria. Subjects with asymptomatic pyelonephritis had inferior graft survival compared to the matched cohort HR 1.88 (1.06–3.35), p = .0281. In addition, of these 123 subjects, 68 (55%) subsequently developed pyelonephritis, and 34 subjects had pyelonephritis within 6 months after this episode. Subjects with recurrent infections exhibited lower survival HR 2.86 (1.36–6.02) and a trend toward higher rejection risk.ConclusionAsymptomatic histologic pyelonephritis can occur in kidney transplant recipients and is associated with inferior graft survival.

ImportanceLip, oral, and pharyngeal cancers are important contributors to cancer burden worldwide, and a comprehensive evaluation of their burden globally, regionally, and nationally is crucial for effective policy planning.ObjectiveTo analyze the total and risk-attributable burden of lip and oral cavity cancer (LOC) and other pharyngeal cancer (OPC) for 204 countries and territories and by Socio-demographic Index (SDI) using 2019 Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study estimates.Evidence ReviewThe incidence, mortality, and disability-adjusted life years (DALYs) due to LOC and OPC from 1990 to 2019 were estimated using GBD 2019 methods. The GBD 2019 comparative risk assessment framework was used to estimate the proportion of deaths and DALYs for LOC and OPC attributable to smoking, tobacco, and alcohol consumption in 2019.FindingsIn 2019, 370 000 (95% uncertainty interval [UI], 338 000-401 000) cases and 199 000 (95% UI, 181 000-217 000) deaths for LOC and 167 000 (95% UI, 153 000-180 000) cases and 114 000 (95% UI, 103 000-126 000) deaths for OPC were estimated to occur globally, contributing 5.5 million (95% UI, 5.0-6.0 million) and 3.2 million (95% UI, 2.9-3.6 million) DALYs, respectively. From 1990 to 2019, low-middle and low SDI regions consistently showed the highest age-standardized mortality rates due to LOC and OPC, while the high SDI strata exhibited age-standardized incidence rates decreasing for LOC and increasing for OPC. Globally in 2019, smoking had the greatest contribution to risk-attributable OPC deaths for both sexes (55.8% [95% UI, 49.2%-62.0%] of all OPC deaths in male individuals and 17.4% [95% UI, 13.8%-21.2%] of all OPC deaths in female individuals). Smoking and alcohol both contributed to substantial LOC deaths globally among male individuals (42.3% [95% UI, 35.2%-48.6%] and 40.2% [95% UI, 33.3%-46.8%] of all risk-attributable cancer deaths, respectively), while chewing tobacco contributed to the greatest attributable LOC deaths among female individuals (27.6% [95% UI, 21.5%-33.8%]), driven by high risk-attributable burden in South and Southeast Asia.Conclusions and RelevanceIn this systematic analysis, disparities in LOC and OPC burden existed across the SDI spectrum, and a considerable percentage of burden was attributable to tobacco and alcohol use. These estimates can contribute to an understanding of the distribution and disparities in LOC and OPC burden globally and support cancer control planning efforts.